UBUNTU-CVE-2026-43994

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Source
https://ubuntu.com/security/CVE-2026-43994
Import Source
https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json
JSON Data
https://api.osv.dev/v1/vulns/UBUNTU-CVE-2026-43994
Upstream
Published
2026-06-18T21:16:00Z
Modified
2026-06-29T13:50:24.255548781Z
Severity
  • 8.1 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
  • 9.8 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
  • Ubuntu - medium
Summary
[none]
Details

Coturn is a free open source implementation of TURN and STUN Server. Versions prior to 4.10.0 contain a stack buffer overflow in decodeoauthtokengcm(). A uint16t noncelen field read from an attacker-supplied OAuth access token (0-65535) is passed directly to memcpy() as the copy length into a 256-byte stack buffer (oauthencrypted_block.nonce[256]) without bounds checking. The overflow occurs before AES-GCM authentication is verified, the attacker does not need to know the OAuth key or produce a valid AES-GCM token. Up to 735 bytes of attacker-controlled data are written past the buffer, may corrupt adjacent stack data, including control-flow data depending on compiler, ABI, and mitigations. Requires --oauth mode (non-default). This may provide a plausible RCE primitive depending on exploit mitigations; because coturn is widely deployed for WebRTC TURN/STUN and --oauth is commonly recommended, impact can be broad. This issue has been fixed in version 4.10.0.

References

Affected packages

Ubuntu:16.04:LTS
coturn

Package

Name
coturn
Purl
pkg:deb/ubuntu/coturn?arch=source&distro=xenial

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*
4.4.5.4-2
4.5.0.2-3
4.5.0.3-1
4.5.0.3-1build1
4.5.0.3-1ubuntu0.2
4.5.0.3-1ubuntu0.3
4.5.0.3-1ubuntu0.4

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "coturn",
            "binary_version": "4.5.0.3-1ubuntu0.4"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json"
Ubuntu:18.04:LTS
coturn

Package

Name
coturn
Purl
pkg:deb/ubuntu/coturn?arch=source&distro=bionic

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*
4.5.0.6-1ubuntu2
4.5.0.7-1ubuntu1
4.5.0.7-1ubuntu2
4.5.0.7-1ubuntu2.18.04.1
4.5.0.7-1ubuntu2.18.04.2
4.5.0.7-1ubuntu2.18.04.3

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "coturn",
            "binary_version": "4.5.0.7-1ubuntu2.18.04.3"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json"
Ubuntu:20.04:LTS
coturn

Package

Name
coturn
Purl
pkg:deb/ubuntu/coturn?arch=source&distro=focal

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*
4.5.1.1-1.1build1
4.5.1.1-1.1build2
4.5.1.1-1.1ubuntu0.20.04.1
4.5.1.1-1.1ubuntu0.20.04.2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "coturn",
            "binary_version": "4.5.1.1-1.1ubuntu0.20.04.2"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json"
Ubuntu:22.04:LTS
coturn

Package

Name
coturn
Purl
pkg:deb/ubuntu/coturn?arch=source&distro=jammy

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*
4.5.2-3
4.5.2-3.1~ubuntu22.04.1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "coturn",
            "binary_version": "4.5.2-3.1~ubuntu22.04.1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json"
Ubuntu:24.04:LTS
coturn

Package

Name
coturn
Purl
pkg:deb/ubuntu/coturn?arch=source&distro=noble

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*
4.6.1-1build1
4.6.1-1build2
4.6.1-1build3
4.6.1-1build4

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "coturn",
            "binary_version": "4.6.1-1build4"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json"
Ubuntu:25.10
coturn

Package

Name
coturn
Purl
pkg:deb/ubuntu/coturn?arch=source&distro=questing

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*
4.6.1-2build1

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "coturn",
            "binary_version": "4.6.1-2build1"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json"
Ubuntu:26.04:LTS
coturn

Package

Name
coturn
Purl
pkg:deb/ubuntu/coturn?arch=source&distro=resolute

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected

Affected versions

4.*
4.6.1-2build1
4.6.1-2build2

Ecosystem specific 

{
    "binaries": [
        {
            "binary_name": "coturn",
            "binary_version": "4.6.1-2build2"
        }
    ]
}

Database specific

source 
"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-43994.json"